Flame-retardant abs graft polymer blends



United States Patent US. Cl. 260880 6 Claims ABSTRACT OF THE DISCLOSUREFlame-retardant graft polymer blends of halogen-substituted carboxylicacids and/or acid anhydrides with acrylonitrile-butadiene-styrene graftpolymer compositions.

This invention relates to flame-retardant graft polymer blends and moreparticularly to flame-retardant graft polymer blends ofhalogen-substituted carboxylic acids and/or acid anhydrides with ABSgraft polymer materials.

It is well known that many of the graft polymer blends are inherentlyflammable, and for this reason, are somewhat limited in certainapplications. For example, applications Which require fireproofmaterials, such as construction materials, are limited toflame-retardant graft polymers. Many attempts have been made to rendergraft polymers flame-retardant by adding flame-retardant additives aswell as by blending with flame-resistant materials. The addition of manyof these flame-retardant materials to graft polymers has resulted inalteration of their physical and chemical properties as Well asprocessing characteristics. Addition of some of the chlorinatedmaterials, such as polyvinyl chloride, has also had a tendency tosubstantially reduce their processing temperatures and when the graftpolymers are compounded with a significant amount of chlorinatedcompound therein, it is necessary to process at comparatively lowtemperatures. Also, it should be noted that if normal ABS processingtemperatures are utilized, a certain amount of degradation occurs in thechlorinated portion of the blending components.

It has been found that halogen-substituted carboxylic acids and/ or acidanhydrides may be added to ABS graft polymers to substantially improvetheir flame-resistant properties with little or no change in theirphysical properties. It has further been found that thehalogen-substituted carboxylic acids and/ or acid anhydrides may beblended with ABS graft polymer within the normal processing temperaturesof the graft polymers.

Generally stated, this invention is directed to the blending ofchloroand/or bromo-substituted carboxylic acids and/ or acid anhydrideswith a variety of ABS graft polymers to improve upon theirflame-retardant properties. From about 1 to 10 percent by weight ofcompounds that are knOWn to contribute to flame-retardancy, such asantimony oxide and other antimony compounds, may also be added to theblend. The blends of this invention may be compounded and molded eventhough they contain large amounts of chlorine or bromine, at relativelyhigh temperatures. It is especially significant that the blends of thisinvention may be compounded and will remain stable under normalprocessing conditions.

When blending the halogen-substituted carboxylic acids and/ or acidanhydride with ABS graft polymers, the acid and/or anhydride may beblended in amounts from about percent by Weight to about 50 percent byweight of the total composition, and preferably in amounts from about 5to about 25 percent by weight of the total composition. The graftcopolymer correspondingly will comprise from about 94 percent by weightto about 50 percent by weight of the total composition. It has beenfound that additional flame-retardant materials or materials whichcontribute to flame-retardancy, such as antimony oxide, may be added inamounts from about 1 to about 10 percent by Weight of the totalcomposition.

The preferred halogen-substituted carboxylic acids and/or acid anhydrideis l,2,3,4,9,9-hexachloro-1,4,4a,5,6,7,8,8a-octahydro-1,4-methenonaphthalene 6,7 dicarboxylic acidanhydride. Other halo-substituted compounds such as5,6,7,8,9,9-hexachloro 1,2,3,4,4a,5,8,8a octahydro 5,8 metheno 2,3naphthalenedicarboxylic acid; 5,6,7,8,9,9 hexachloro 2 carboxyl,2,3,4,4a,5,8,8a octahydro 5,8 metheno-2-naphthaleneacetic acid; 5,6,7,8,9,9-hexachloro 3 carboxy 1,2,3,4,4a,5,8,8a-octahydro 5,8metheno-2-naphthaleneacetic acid; 5,6,7,8,9,9- hexachloro1,2,3,4,4a,5,8,8a-octahydro 5,8-metheno-2 naphthalene succinic acid;5,6,7,8,9,9-hexachloro-1,2,3, 4,4a,5,8,8a octahydro 5,8-metheno 2naphthalenemalonic acid; 5,6,7,8,9,9 hexabromo1,2,3,4,4a,5,8,8aoctahydro 5,8 metheno 2,3 naphthalenedicarboxylic acid;5,6,7,8,9,9 hexabromo 2 carboxy-1,2,3,4,4a,5,8, 8a octahydro 5,8-metheno2 naphthaleneacetic acid; 5,6,7,8,9,9 hexabromo l,2,34,4a,5,8,8aoctahydro-5,8- metheno 2 naphthalene-succinic acid, and the like mayalso be used. The chlorine and bromine substituted carboxylic acidsand/or acid anhydrides of this invention may be prepared by theDiels-Alder addition of hexahalocyclopentadiene and tetrahydrophthalicanhydride or derivatives of the anhydride. The preferred method ofpreparing these compounds may be obtained from United States Patent3,152,172 wherein hexachlorocyclopentadiene is reacted withtetrahydrophthalic anhydride and derivatives thereof.

The graft polymers utilized in this invention are those prepared fromconjugated diene, monovinyl aromatic hydrocarbon and acrylic acidnitrile monomer. A graft polymer is a polymer prepared by firstpolymerizing a monomer (or mixture of monomers) with subsequentpolymerization of a second monomer or group of monomers onto the productof the first polymerization. The first polymerization prepares what ishereinafter referred to as the rubbery backbone.

The specific graft polymers utilized in this invention are prepared byfirst polymerizing a conjugated diene, such as butadiene, or aconjugated diene in the presence of a monovinyl aromatic hydrocarbonsuch as styrene, to provide a polymerized diene rubbery backbone such aspolybutadiene or a butadiene-styrene copolymer backbone. Thereafter, asecond set of monomers are grafted to the rubbery backbone to completethe graft polymer. This is accomplished by the addition and interactionunder polymerizing conditions of an acrylic acid nitrile monomer ormonomers and a vinyl aromatic hydrocarbon monomer or monomersexemplified respectively by acrylonitrile and styrene.

The backbone, i.e., conjugated diene polymer or copolymer, is preparedso as to comprise from about 60 percent to about 10 percent by Weight ofthe total composition and the acrylic acid nitrile and aromaticmonovinyl hydrocarbon that is polymerized in the presence of thebackbone polymer of copolymer comprises from about 40 percent to about90 percent by weight of the total composition.

The acrylic acid nitrile preferably, comprises from about 5 percent toabout 35 percent by Weight of the three-cumponent organic mixture andthe monovinyl aromatic hydrocarbon comprises from about 30 percent toabout percent of the total composition.

The term monovinyl aromatic hydrocarbon is meant to include compoundssuch as styrene, a-methylstyrene, vinyl toluene, vinyl xylene,ethylvinylbenzene, isopropyl styrene, chlorostyrene, dichlorostyrene,ethylchlorostyrene, mixtures thereof and the like. The acrylic acidnitrile compounds include compounds such as acrylonitrile,methacrylonitrile, ethacrylonitrile, chloroacrylonitrile, mixturesthereof and the like.

The specific graft polymers utilized in the examples substituted toprepare the graft polymers, e.g., a styrenebutadiene substrate may besubstituted for the polybutadiene.

The examples set forth in the tables below were prepared by firstpolymerizing the monomers above-mentioned to ranged from compositlonscontaining about 10 percent by prepare the graft polymer w1th subsequentblending of the weight to about 50 percent by weight of polybutadieneABS graft polymers and halogen-substituted carboxylic with from about 20percent to about 30 percent by weight acids and/ or acid anhydride in aBanbury mixer. The exacrylonitrile, and from about 30 percent to about60 peramples are meant to illustrate the blends of this invention centby Weight styrene polymerized in the presence of m and are not intendedto limit the generally broad scope polybutadiene. As mentioned, othermonomers may be thereof. All parts are by weight unless otherwiseindicated.

TABLE 1 Graft Polymer of 51% Stryene, 20% Acrylonitrile, 20% Butadiene100 95 00 85 80 751,2,3,4,0,9-l1exachloro-1,4,4a,5,6,7,8,Ba-octahydrod,4-methenonaphthalene-Gfldicarboxylieanhydride 5 Antimony Oxide 0 0 0 0 0 0 Dibutyl Tin Maleate 2. 0 2. 0 2.0 2. 0 2. 0 2. 0 Lubricant 1.0 1.0 1.0 1.0 1.0 1.0 Tensile (p.s.i. atyeidl), L/B spcimen, ASTM D-638-61, 0.2/Minute... 6, 000 6, 100 6,2006,250 6, 300 6, 150 Elongation (percent) 95 25 15 15 1 HDT x y, at 16p.s.i. F.) 210 218 216 206 205 200 HDT x at 264 psi. F.)1 198 188 184178 182 180 Melt Index at 410 F 0. 8A1 1. 4A1 2. 2111 1. my. 1. 6B1 2.7B1 Rockwell Hardness R, ASTM D-785-62, Method A, Specimen"..- 105 105105 104 104 102 Flcxural Modulus (X105), W x 1" x 4 bars tested at 73F., ASTM D-790-61, 0.05/Minute 3.2 3. 4 3. 3 3. 5 3. 7 4. 0 4.1 FlexuralStrength (p.s.i.) 9, 600 0, 000 10, 300 10, 600 0, 050 9, 000 6, 000Notched Izod Impact (73 F. in ft. lbs/in. of notch), W specimen,

ASTM D-256-56, Method A 6. 2 6. 1 6. 1 4. 9 2.1 1. 4 0. 7 ASTMFlammability 2 1. 1. 46 1. 38 1. 34 1. 35 nb 1113 nl) 1 Unannealed x x5" bars, F. at 10 mils deflection.

Z Flamability of rigid plastics over 0050" thickness. AS'IM D-636-56T.Values will be in inches/minute, seli-cxtinguisl1ing (so) or non-burning(11b).

TABLE 2 Graft Polymer of 51% Styrene, 29% Aerylonitrile, 20% Butadieuen.05 751,2,3,4,9,0-hexachloro-1,4,4a,5,6,7,8,8a-0ctahydr0-l,4-metl1enonaphthalene-ofl-dicarboxylicanhydi'ide 5 15 25 10 Antimony Oxide 1.0 1.0 1 0 7 Dibutyl Tin Maleate2. 0 2.0 2. 0 2, Lubricant 1. 0 1. 0 1. 0 1. 0 Tensile (p.s.i. atyield), specimen, ASTM D-638-61, 0.2lMinute... 6,250 6,400 6, 250 6,Elongation (percent) 50 15 6 2 HDT x V at 16 p.s.i. RM. 214 209 200 HDTV 11 V at 264 p.s.i. F.) 184 183 185 Melt Index at 410 F 1 711% 2.5131 23A1 Rockwell Hardness R, ASTM D-785-62, Method A, M specimem. 104 104 1Flexural Modulus (X10 x 1" x 4" bars tested at 73 F. ASTM D- 790-01,0.05"] 3. 3 3. 4 3. Q 3. 5 Flexnral Strength (p.s.i.) 10, 250 10,4008,700 10, 300 Notched Izod Impact (73 F. 1n it. lbs/1n. of notch),specimen,

ASTM D25656, Method A 4. 4 3. 0 1. 3 1. 8 AS'IM Flammability 1 1. 25 0.98 I11) 0. 98

1 Unannealed x x 5" bars, F. at 10 mils deflection. gilammability ofRigid Plastics over 0.050 thickness. ASTM D-636-56T. Values will TABLE 3be in inches/minute, self-extinguishing (se) or non-burning GraftPolymer 01 51% Styrene, 29% Acrylonitirle, 20% Butadiene 85 80 75 95 8575 65 501,2,3,4,9,9-hexachloro-1,4,4a,5,6,7,8,8a-octahydro-l,4-n1ethenonaphthalene-fifi-dicarboxylicanhydride 15 20 25 5 15 25 35 50 Antimony Oxide 7 7 7 10 10 10 10 10Dibutyl Tin Maleate- 2. 0 2. 0 2.0 2. 0 2. 0 2. 0 2.0 2. 0 Lubricant 1.0 1. 0 1. 0 1. 0 1. 0 1. 0 1. 0 1. 0 Tensile (p.s.i. at yield), X,specimen, ASTM D-638-611, 0.2/m1nute 6, 100 6, 300 6, 400 6, 300 6, 4006, 300 5, 500 Elongation (percent) 2 8 6 25 10 7 4 HDT x V at 16 11.8.1F.) 208 199 207 214 207 207 213 EDT x at 264 p.s.i. F.). 180 176 184 188181 189 Melt Index at 410 F 1. 811% 1. SE1 2 3B1 1. 2A1 1. 711% 2.4131 1. 713% Rockwell Hardness R, ASTM D-785-62, Method A, specimen..."104 104 102 104 104 101 100 Flexural Modulus (X10 M 11 1" x 4 barstested at 73 F., ASTM D 790-61, 0.05"/minute 3. 6 3. 8 3. 8 3. 5 3. 7 4.1 4. Flexural Strength (p.s.i.) 10, 550 10, 000 8, 600 9, 700 10, 500 8,600 7, 400 Notched Izod Impact (73 F. in it. lbs/in. of notch), 54;specimen,

ASTM D25656, Method A- 1. 4 1. 2 0.9 2.0 1.3 1. 0 0.5 ASTM Flammability11b nb nb 1. 20 uh uh uh nb l Unannealed x x 5 bars, F. at 10 milsdeflection.

2 Flammability of rigid plastics over 0.050 thickness. ASTM D-63G-56'1.Values will be in inches/minute, selt extinguishing (se) or non-burning(11b) TABLE 4 25 26 27 28 29 30 31 32 Graft Polymer of 35% Styrene, 18%Acrylonitrile, 47% Butadiene 100 95 8 75 65 50 65 501,2,3,4,9,9-l1exachloro-l,4,4a,5,6,7,8,8a-octahydro-1,4-methenonaphthalene-6,7-dicarboxylicanhydride 5 Antimony Oxide Dibutyl Tin Male 2.0 2.0 2.0 Lubricant. 1.01.0 1.0 Tensile (p yield) 2, 300 2, 400 2, 550 Elongation (percent) 168161 140 HDT K M at 16 p. 199 195 202 HDT x at 264 p 146 158 163 MeltIndex at 410 F 03113 0. 2A3 0. 3A3 65 65 68 1. 2 1. 4 1. 7 FleiuralStrength (p s 1 3, 950 4, 05 3, 950 Notched Izod Impact. 8. 2 7. 6 4. 9ASTM Flammability 1. 1.11 0. 81

For explanation of physical tests, see Tables 1, 2, and 3.

TABLE 5 33 34 35 36 37 Graft Polymer of 35% Styrene; 18% Acrylonitrile;47%

Butadiene 95 85 75 65 5O 1,2,3,4,9,9-hexachloro-1,,5,6,7,8,8a-octahydro-1,4

methenonaphthalene 7-dicarboxylic anhydride 5 15 25 35 Antimony O.:idc.- 7 7 7 10 Dibutyl Tin Maleate 2. O 2. 0 2. 0 2. 0 Lubricant 1.01.0 1.0 1.0 Tensile (p.s.i. at yield) 2, 300 2, 450 2, 600 2, 550Elongation (per cent) 155 180 120 15 HDT x at 16 p.s.i. F. 200 197 204204 EDT A x V at 264 p.s.i. F 158 160 164 168 Melt Index at 410 F 04.430. 2A3 0. 6A3 0. 3A1 Shore D Hardness, ASTM D-1706-59T- 65 65 67 7OFlexural Modulus (X10 1. 2 1. 4 1. 6 1. 8 Floxural Strength (p.s.i.) 3,950 4, 100 3, 750 3, 950 Notched Izod Impact- 8. 2 7. 7 4. 2 1. 2 ASTMFlammability 1. 25 111) nb nb For explanation of physical tests, seeTables 1, 2, and 3.

TABLE 6 38 39 40 41 42 43 44 Graft Polymer of 57% Styrene, 31%Acrylonitrile, 12%

Butadiene 100 95 85 75 95 85 75 1,2,2,3,4,9,9,-hexachloro-,5,6,7,8,8a-octahydro-1,4-

methenonaphthalene-6 7-dicarboxylic anhydride 5 15 25 5 15 25 AntimonyOxide 7 7 7 Dibutyl Tin Maleate 2. 0 2. 0 2. 0 2. 0 2. 0 2. 0 2. 0Lubricant 1. 0 1. 0 1. 0 1. 0 1. 0 1. 0 1. 0 Tensile (p.s.i. at yield)-7, 800 8, 000 8, 100 6, 850 8, 050 8, 150 6, 850 Elongation (percent) 2025 10 4 20 10 4 HD'I x /2 at 16 p.s.i. F.) 217 216 207 210 217 205 209HDT x at 264 p.s.i. F.) 193 193 184 187 192 181 188 Melt Index at 410 F0. 4B1 2. 0A1 2. 011 *TF 1. 8A1 1. 311% 1. 7B% Rockwell Hardness R 112114 118 110 112 110 Flexural Modulus (X10 4. 4.0 4. 2 4. 7 4. 4. 4. 6Flexural Strength (p.s.i.) 12,400 12,900 13,350 11,600 12,800 12, 60010,700 Notched Izod Impact- 1.4 1. 1 0.8 0.5 0.8 0. 8 0.6 ASTMFlammability 1. 1. 59 1. 39 Se 1. 38 uh uh For explanation of physicaltests, see Tables 1, 2, and

*Too fast for test.

In the examples, the polymeric blends were prepared 50 from graftpolymers containing polybutadiene rather than polybutadiene-styrenecopolymers, however, as indicated, these graft polymers are equallyapplicable to this invention. It will be noted that the physicalproperties are not greatly altered through addition of high chlorinecontent materials and the flame-retardancy of the resulting blend is farsuperior to that of the graft polymers by themselves.

It should be understood that while this invention has been described inconnection with certain specific blends containing specific amounts ofchlorinated acids and/or anhydrides, that this is by way of illustrationand not limitation, and that the scope of the invention is definedsolely by the appended claims which should be construed as broadly as isconsistent with the prior art.

What is claimed is:

and from about 95 to about 50 percent by weightacrylonitrile-butadiene-styrene graft polymer.

2. The thermoplastic flame-retardant blend of claim 1 1. Athermoplastic, flame-retardant blend, comprising from about 5 to about50 percent by weight of chlorine and bromine substituted carboxylicacids and/or acid anhydrides selected from the group consisting ofwherein the chlorine and bromine substituted carboxylic acid and/or acidanhydride comprises from about 5 to about 25 percent by weight of thetotal composition, and the graft polymer correspondingly comprises fromabout 75 to about percent by weight of the total composition.

3. The thermoplastic blend of claim 1 wherein the graft polymer isprepared by polymerizing a conjugated diene and thereafter polymerizinga monovinyl aromatic hydrocarbon and an acrylic acid nitrile in thepresence of said conjugated diene.

4. The thermoplastic blend of claim 1 wherein the graft polymer isprepared by polymerizing from about 40 percent to about 90 percent byWeight of a monovinyl aromatic hydrocarbon and an acrylic acid nitrilein the presence of from about 10 percent to about 60 percent by Weightof a polymerized product selected from the group consisting ofconjugated diene homopolymers and conjugated diene-monovinyl aromatichydrocarbon copolymers.

5. The thermoplastic blend of claim 1 wherein the chlorine and brominesubstituted dicarboxylic acid anhydride is1,2,3,4,9,9-hexachloro-1,4,4a,5,6,7,8,Sa-octahydro-1,4-methanonaphthalone-6,7-dicarboxylic anhydride.

6. The thermoplastic blend of claim 1 wherein an antimony oxideflame-retardant material is added in an amount References Cited UNITEDSTATES PATENTS GEORGE F. LESMES, Primary Examiner.

US. Cl. X.R.

of from about 1 percent to 10 percent of the total 15 346-6 composition.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No.3,442,980 May 6, i969 Thomas S. Grabowski It is certified that errorappears in the above identified patent and that said Letters Patent arehereby corrected as shown below:

Column 5; line 72, "5,6,7,8,9 should read 5,6,7,8,9,9 line 74,"l,2,3,4,4,5,8,8a-" should read l,2,3,4,4a,5,8,8a-

Signed and sealed this 14th day of April 1970.

(SEAL) Attest:

WILLIAM E. SCHUYLER, JR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer

